Network connection automatically keeps down and up

Issues related to configuring your network
Post Reply
qidizi
Posts: 4
Joined: 2015/02/14 11:08:58

Network connection automatically keeps down and up

Post by qidizi » 2015/02/14 11:49:51

Oracle VM VirtualBox 4.3.22+Network interface type is "NAT" + intel PRO/1000 T server (82543GC)
CentOS Linux release 7.0.1406 (Core)
Linux qidiziCentos.localdomain 3.10.0-123.20.1.el7.x86_64 #1 SMP Thu Jan 29 18:05:33 UTC 2015 x86_64 x86_64 x86_64 GNU/Linux

cat /var/log/message
tworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) started...
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-config -> ip-check (reason 'none') [70 80 0]
Feb 14 19:15:54 qidiziCentos avahi-daemon[531]: Joining mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:15:54 qidiziCentos avahi-daemon[531]: New relevant interface enp0s3.IPv4 for mDNS.
Feb 14 19:15:54 qidiziCentos avahi-daemon[531]: Registering new address record for 10.0.2.15 on enp0s3.IPv4.
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) complete.
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-check -> secondaries (reason 'none') [80 90 0]
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: secondaries -> activated (reason 'none') [90 100 0]
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTED_LOCAL
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> Policy set 'Wired connection 1' (enp0s3) as default for IPv4 routing and DNS.
Feb 14 19:15:54 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) successful, device activated.
Feb 14 19:15:55 qidiziCentos avahi-daemon[531]: Registering new address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.*.
Feb 14 19:18:15 qidiziCentos kernel: e1000: enp0s3 NIC Link is Down
Feb 14 19:18:15 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (deferring action for 4 seconds)
Feb 14 19:18:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (calling deferred action)
Feb 14 19:18:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: activated -> unavailable (reason 'carrier-changed') [100 20 40]
Feb 14 19:18:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): deactivating device (reason 'carrier-changed') [40]
Feb 14 19:18:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 3382
Feb 14 19:18:19 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now DISCONNECTED
Feb 14 19:18:19 qidiziCentos avahi-daemon[531]: Withdrawing address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.
Feb 14 19:18:19 qidiziCentos avahi-daemon[531]: Withdrawing address record for 10.0.2.15 on enp0s3.
Feb 14 19:18:19 qidiziCentos avahi-daemon[531]: Leaving mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:18:19 qidiziCentos avahi-daemon[531]: Interface enp0s3.IPv4 no longer relevant for mDNS.
Feb 14 19:18:19 qidiziCentos dbus-daemon: dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:18:19 qidiziCentos dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:18:19 qidiziCentos systemd: Starting Network Manager Script Dispatcher Service...
Feb 14 19:18:19 qidiziCentos dbus-daemon: dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:18:19 qidiziCentos dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:18:19 qidiziCentos systemd: Started Network Manager Script Dispatcher Service.
Feb 14 19:18:21 qidiziCentos kernel: e1000: enp0s3 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
Feb 14 19:18:21 qidiziCentos kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp0s3: link becomes ready
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): link connected
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Auto-activating connection 'Wired connection 1'.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) starting connection 'Wired connection 1'
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) scheduled...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) started...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTING
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) scheduled...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) complete.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) starting...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) successful.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) complete.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) scheduled.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) started...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> dhclient started with pid 3437
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) complete.
Feb 14 19:18:21 qidiziCentos dhclient[3437]: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:18:21 qidiziCentos dhclient[3437]: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:18:21 qidiziCentos dhclient[3437]: All rights reserved.
Feb 14 19:18:21 qidiziCentos dhclient[3437]: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:18:21 qidiziCentos dhclient[3437]:
Feb 14 19:18:21 qidiziCentos NetworkManager: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:18:21 qidiziCentos NetworkManager: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:18:21 qidiziCentos NetworkManager: All rights reserved.
Feb 14 19:18:21 qidiziCentos NetworkManager: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:18:21 qidiziCentos dhclient[3437]: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:18:21 qidiziCentos dhclient[3437]: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:18:21 qidiziCentos dhclient[3437]: Sending on Socket/fallback
Feb 14 19:18:21 qidiziCentos dhclient[3437]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x42616c8b)
Feb 14 19:18:21 qidiziCentos NetworkManager: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:18:21 qidiziCentos NetworkManager: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:18:21 qidiziCentos NetworkManager: Sending on Socket/fallback
Feb 14 19:18:21 qidiziCentos NetworkManager: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x42616c8b)
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed nbi -> preinit
Feb 14 19:18:21 qidiziCentos dhclient[3437]: DHCPACK from 10.0.2.2 (xid=0x42616c8b)
Feb 14 19:18:21 qidiziCentos NetworkManager: DHCPACK from 10.0.2.2 (xid=0x42616c8b)
Feb 14 19:18:21 qidiziCentos dhclient[3437]: bound to 10.0.2.15 -- renewal in 42810 seconds.
Feb 14 19:18:21 qidiziCentos NetworkManager: bound to 10.0.2.15 -- renewal in 42810 seconds.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed preinit -> reboot
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> address 10.0.2.15
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> plen 24 (255.255.255.0)
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> gateway 10.0.2.2
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> server identifier 10.0.2.2
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> lease time 86400
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> nameserver '202.106.46.151'
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> nameserver '8.8.8.8'
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Configure Commit) scheduled...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) started...
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-config -> ip-check (reason 'none') [70 80 0]
Feb 14 19:18:21 qidiziCentos avahi-daemon[531]: Joining mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:18:21 qidiziCentos avahi-daemon[531]: New relevant interface enp0s3.IPv4 for mDNS.
Feb 14 19:18:21 qidiziCentos avahi-daemon[531]: Registering new address record for 10.0.2.15 on enp0s3.IPv4.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) complete.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-check -> secondaries (reason 'none') [80 90 0]
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: secondaries -> activated (reason 'none') [90 100 0]
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTED_LOCAL
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Policy set 'Wired connection 1' (enp0s3) as default for IPv4 routing and DNS.
Feb 14 19:18:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) successful, device activated.
Feb 14 19:18:22 qidiziCentos avahi-daemon[531]: Registering new address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.*.
Feb 14 19:20:12 qidiziCentos kernel: e1000: enp0s3 NIC Link is Down
Feb 14 19:20:12 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (deferring action for 4 seconds)
Feb 14 19:20:16 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (calling deferred action)
Feb 14 19:20:16 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: activated -> unavailable (reason 'carrier-changed') [100 20 40]
Feb 14 19:20:16 qidiziCentos NetworkManager[642]: <info> (enp0s3): deactivating device (reason 'carrier-changed') [40]
Feb 14 19:20:16 qidiziCentos NetworkManager[642]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 3437
Feb 14 19:20:16 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now DISCONNECTED
Feb 14 19:20:16 qidiziCentos avahi-daemon[531]: Withdrawing address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.
Feb 14 19:20:16 qidiziCentos avahi-daemon[531]: Withdrawing address record for 10.0.2.15 on enp0s3.
Feb 14 19:20:16 qidiziCentos avahi-daemon[531]: Leaving mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:20:16 qidiziCentos avahi-daemon[531]: Interface enp0s3.IPv4 no longer relevant for mDNS.
Feb 14 19:20:16 qidiziCentos dbus-daemon: dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:20:16 qidiziCentos dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:20:16 qidiziCentos systemd: Starting Network Manager Script Dispatcher Service...
Feb 14 19:20:16 qidiziCentos dbus-daemon: dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:20:16 qidiziCentos dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:20:16 qidiziCentos systemd: Started Network Manager Script Dispatcher Service.
Feb 14 19:20:18 qidiziCentos kernel: e1000: enp0s3 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
Feb 14 19:20:18 qidiziCentos kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp0s3: link becomes ready
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): link connected
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Auto-activating connection 'Wired connection 1'.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) starting connection 'Wired connection 1'
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) scheduled...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) started...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTING
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) scheduled...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) complete.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) starting...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) successful.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) complete.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) scheduled.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) started...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> dhclient started with pid 3494
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) complete.
Feb 14 19:20:18 qidiziCentos dhclient[3494]: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:20:18 qidiziCentos dhclient[3494]: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:20:18 qidiziCentos dhclient[3494]: All rights reserved.
Feb 14 19:20:18 qidiziCentos dhclient[3494]: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:20:18 qidiziCentos dhclient[3494]:
Feb 14 19:20:18 qidiziCentos NetworkManager: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:20:18 qidiziCentos NetworkManager: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:20:18 qidiziCentos NetworkManager: All rights reserved.
Feb 14 19:20:18 qidiziCentos NetworkManager: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:20:18 qidiziCentos dhclient[3494]: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:20:18 qidiziCentos dhclient[3494]: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:20:18 qidiziCentos dhclient[3494]: Sending on Socket/fallback
Feb 14 19:20:18 qidiziCentos dhclient[3494]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x6fac6e2d)
Feb 14 19:20:18 qidiziCentos NetworkManager: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:20:18 qidiziCentos NetworkManager: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:20:18 qidiziCentos NetworkManager: Sending on Socket/fallback
Feb 14 19:20:18 qidiziCentos NetworkManager: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x6fac6e2d)
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed nbi -> preinit
Feb 14 19:20:18 qidiziCentos dhclient[3494]: DHCPACK from 10.0.2.2 (xid=0x6fac6e2d)
Feb 14 19:20:18 qidiziCentos NetworkManager: DHCPACK from 10.0.2.2 (xid=0x6fac6e2d)
Feb 14 19:20:18 qidiziCentos dhclient[3494]: bound to 10.0.2.15 -- renewal in 42983 seconds.
Feb 14 19:20:18 qidiziCentos NetworkManager: bound to 10.0.2.15 -- renewal in 42983 seconds.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed preinit -> reboot
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> address 10.0.2.15
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> plen 24 (255.255.255.0)
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> gateway 10.0.2.2
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> server identifier 10.0.2.2
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> lease time 86400
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> nameserver '202.106.46.151'
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> nameserver '8.8.8.8'
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Configure Commit) scheduled...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) started...
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-config -> ip-check (reason 'none') [70 80 0]
Feb 14 19:20:18 qidiziCentos avahi-daemon[531]: Joining mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:20:18 qidiziCentos avahi-daemon[531]: New relevant interface enp0s3.IPv4 for mDNS.
Feb 14 19:20:18 qidiziCentos avahi-daemon[531]: Registering new address record for 10.0.2.15 on enp0s3.IPv4.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) complete.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-check -> secondaries (reason 'none') [80 90 0]
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: secondaries -> activated (reason 'none') [90 100 0]
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTED_LOCAL
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Policy set 'Wired connection 1' (enp0s3) as default for IPv4 routing and DNS.
Feb 14 19:20:18 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) successful, device activated.
Feb 14 19:20:19 qidiziCentos avahi-daemon[531]: Registering new address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.*.
Feb 14 19:20:19 qidiziCentos systemd: Starting Session 3 of user qidizi.
Feb 14 19:20:19 qidiziCentos systemd: Started Session 3 of user qidizi.
Feb 14 19:20:19 qidiziCentos systemd-logind: New session 3 of user qidizi.
Feb 14 19:20:19 qidiziCentos su: (to root) qidizi on pts/0
Feb 14 19:22:15 qidiziCentos kernel: e1000: enp0s3 NIC Link is Down
Feb 14 19:22:15 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (deferring action for 4 seconds)
Feb 14 19:22:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (calling deferred action)
Feb 14 19:22:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: activated -> unavailable (reason 'carrier-changed') [100 20 40]
Feb 14 19:22:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): deactivating device (reason 'carrier-changed') [40]
Feb 14 19:22:19 qidiziCentos NetworkManager[642]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 3494
Feb 14 19:22:19 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now DISCONNECTED
Feb 14 19:22:19 qidiziCentos avahi-daemon[531]: Withdrawing address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.
Feb 14 19:22:19 qidiziCentos avahi-daemon[531]: Withdrawing address record for 10.0.2.15 on enp0s3.
Feb 14 19:22:19 qidiziCentos avahi-daemon[531]: Leaving mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:22:19 qidiziCentos avahi-daemon[531]: Interface enp0s3.IPv4 no longer relevant for mDNS.
Feb 14 19:22:19 qidiziCentos dbus-daemon: dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:22:19 qidiziCentos dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:22:19 qidiziCentos systemd: Starting Network Manager Script Dispatcher Service...
Feb 14 19:22:19 qidiziCentos dbus-daemon: dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:22:19 qidiziCentos dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:22:20 qidiziCentos systemd: Started Network Manager Script Dispatcher Service.
Feb 14 19:22:21 qidiziCentos kernel: e1000: enp0s3 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
Feb 14 19:22:21 qidiziCentos kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp0s3: link becomes ready
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): link connected
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Auto-activating connection 'Wired connection 1'.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) starting connection 'Wired connection 1'
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) scheduled...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) started...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTING
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) scheduled...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) complete.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) starting...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) successful.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) complete.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) scheduled.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) started...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> dhclient started with pid 3578
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) complete.
Feb 14 19:22:21 qidiziCentos dhclient[3578]: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:22:21 qidiziCentos dhclient[3578]: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:22:21 qidiziCentos dhclient[3578]: All rights reserved.
Feb 14 19:22:21 qidiziCentos dhclient[3578]: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:22:21 qidiziCentos dhclient[3578]:
Feb 14 19:22:21 qidiziCentos NetworkManager: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:22:21 qidiziCentos NetworkManager: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:22:21 qidiziCentos NetworkManager: All rights reserved.
Feb 14 19:22:21 qidiziCentos NetworkManager: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:22:21 qidiziCentos dhclient[3578]: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:22:21 qidiziCentos dhclient[3578]: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:22:21 qidiziCentos dhclient[3578]: Sending on Socket/fallback
Feb 14 19:22:21 qidiziCentos dhclient[3578]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x744cf91)
Feb 14 19:22:21 qidiziCentos dhclient[3578]: DHCPACK from 10.0.2.2 (xid=0x744cf91)
Feb 14 19:22:21 qidiziCentos NetworkManager: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:22:21 qidiziCentos NetworkManager: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:22:21 qidiziCentos NetworkManager: Sending on Socket/fallback
Feb 14 19:22:21 qidiziCentos NetworkManager: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x744cf91)
Feb 14 19:22:21 qidiziCentos NetworkManager: DHCPACK from 10.0.2.2 (xid=0x744cf91)
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed nbi -> preinit
Feb 14 19:22:21 qidiziCentos dhclient[3578]: bound to 10.0.2.15 -- renewal in 33380 seconds.
Feb 14 19:22:21 qidiziCentos NetworkManager: bound to 10.0.2.15 -- renewal in 33380 seconds.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed preinit -> reboot
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> address 10.0.2.15
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> plen 24 (255.255.255.0)
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> gateway 10.0.2.2
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> server identifier 10.0.2.2
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> lease time 86400
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> nameserver '202.106.46.151'
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> nameserver '8.8.8.8'
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Configure Commit) scheduled...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) started...
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-config -> ip-check (reason 'none') [70 80 0]
Feb 14 19:22:21 qidiziCentos avahi-daemon[531]: Joining mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:22:21 qidiziCentos avahi-daemon[531]: New relevant interface enp0s3.IPv4 for mDNS.
Feb 14 19:22:21 qidiziCentos avahi-daemon[531]: Registering new address record for 10.0.2.15 on enp0s3.IPv4.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) complete.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-check -> secondaries (reason 'none') [80 90 0]
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: secondaries -> activated (reason 'none') [90 100 0]
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTED_LOCAL
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Policy set 'Wired connection 1' (enp0s3) as default for IPv4 routing and DNS.
Feb 14 19:22:21 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) successful, device activated.
Feb 14 19:22:22 qidiziCentos avahi-daemon[531]: Registering new address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.*.
Feb 14 19:24:13 qidiziCentos kernel: e1000: enp0s3 NIC Link is Down
Feb 14 19:24:13 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (deferring action for 4 seconds)
Feb 14 19:24:17 qidiziCentos NetworkManager[642]: <info> (enp0s3): link disconnected (calling deferred action)
Feb 14 19:24:17 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: activated -> unavailable (reason 'carrier-changed') [100 20 40]
Feb 14 19:24:17 qidiziCentos NetworkManager[642]: <info> (enp0s3): deactivating device (reason 'carrier-changed') [40]
Feb 14 19:24:17 qidiziCentos NetworkManager[642]: <info> (enp0s3): canceled DHCP transaction, DHCP client pid 3578
Feb 14 19:24:17 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now DISCONNECTED
Feb 14 19:24:17 qidiziCentos avahi-daemon[531]: Withdrawing address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.
Feb 14 19:24:17 qidiziCentos avahi-daemon[531]: Withdrawing address record for 10.0.2.15 on enp0s3.
Feb 14 19:24:17 qidiziCentos avahi-daemon[531]: Leaving mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:24:17 qidiziCentos avahi-daemon[531]: Interface enp0s3.IPv4 no longer relevant for mDNS.
Feb 14 19:24:17 qidiziCentos dbus-daemon: dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:24:17 qidiziCentos dbus[544]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service'
Feb 14 19:24:17 qidiziCentos systemd: Starting Network Manager Script Dispatcher Service...
Feb 14 19:24:17 qidiziCentos dbus-daemon: dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:24:17 qidiziCentos dbus[544]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
Feb 14 19:24:17 qidiziCentos systemd: Started Network Manager Script Dispatcher Service.
Feb 14 19:24:20 qidiziCentos kernel: e1000: enp0s3 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
Feb 14 19:24:20 qidiziCentos kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp0s3: link becomes ready
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): link connected
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: unavailable -> disconnected (reason 'carrier-changed') [20 30 40]
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Auto-activating connection 'Wired connection 1'.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) starting connection 'Wired connection 1'
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) scheduled...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) started...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: disconnected -> prepare (reason 'none') [30 40 0]
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTING
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) scheduled...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 1 of 5 (Device Prepare) complete.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) starting...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: prepare -> config (reason 'none') [40 50 0]
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) successful.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 2 of 5 (Device Configure) complete.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) scheduled.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) started...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: config -> ip-config (reason 'none') [50 70 0]
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Beginning DHCPv4 transaction (timeout in 45 seconds)
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> dhclient started with pid 3633
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 3 of 5 (IP Configure Start) complete.
Feb 14 19:24:20 qidiziCentos dhclient[3633]: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:24:20 qidiziCentos dhclient[3633]: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:24:20 qidiziCentos dhclient[3633]: All rights reserved.
Feb 14 19:24:20 qidiziCentos dhclient[3633]: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:24:20 qidiziCentos dhclient[3633]:
Feb 14 19:24:20 qidiziCentos NetworkManager: Internet Systems Consortium DHCP Client 4.2.5
Feb 14 19:24:20 qidiziCentos NetworkManager: Copyright 2004-2013 Internet Systems Consortium.
Feb 14 19:24:20 qidiziCentos NetworkManager: All rights reserved.
Feb 14 19:24:20 qidiziCentos NetworkManager: For info, please visit https://www.isc.org/software/dhcp/
Feb 14 19:24:20 qidiziCentos dhclient[3633]: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:24:20 qidiziCentos dhclient[3633]: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:24:20 qidiziCentos dhclient[3633]: Sending on Socket/fallback
Feb 14 19:24:20 qidiziCentos dhclient[3633]: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x35958c64)
Feb 14 19:24:20 qidiziCentos dhclient[3633]: DHCPACK from 10.0.2.2 (xid=0x35958c64)
Feb 14 19:24:20 qidiziCentos NetworkManager: Listening on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:24:20 qidiziCentos NetworkManager: Sending on LPF/enp0s3/08:00:27:6a:55:a4
Feb 14 19:24:20 qidiziCentos NetworkManager: Sending on Socket/fallback
Feb 14 19:24:20 qidiziCentos NetworkManager: DHCPREQUEST on enp0s3 to 255.255.255.255 port 67 (xid=0x35958c64)
Feb 14 19:24:20 qidiziCentos NetworkManager: DHCPACK from 10.0.2.2 (xid=0x35958c64)
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed nbi -> preinit
Feb 14 19:24:20 qidiziCentos dhclient[3633]: bound to 10.0.2.15 -- renewal in 42109 seconds.
Feb 14 19:24:20 qidiziCentos NetworkManager: bound to 10.0.2.15 -- renewal in 42109 seconds.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): DHCPv4 state changed preinit -> reboot
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> address 10.0.2.15
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> plen 24 (255.255.255.0)
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> gateway 10.0.2.2
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> server identifier 10.0.2.2
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> lease time 86400
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> nameserver '202.106.46.151'
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> nameserver '8.8.8.8'
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Configure Commit) scheduled...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) started...
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-config -> ip-check (reason 'none') [70 80 0]
Feb 14 19:24:20 qidiziCentos avahi-daemon[531]: Joining mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15.
Feb 14 19:24:20 qidiziCentos avahi-daemon[531]: New relevant interface enp0s3.IPv4 for mDNS.
Feb 14 19:24:20 qidiziCentos avahi-daemon[531]: Registering new address record for 10.0.2.15 on enp0s3.IPv4.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) Stage 5 of 5 (IPv4 Commit) complete.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: ip-check -> secondaries (reason 'none') [80 90 0]
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> (enp0s3): device state change: secondaries -> activated (reason 'none') [90 100 0]
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> NetworkManager state is now CONNECTED_LOCAL
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Policy set 'Wired connection 1' (enp0s3) as default for IPv4 routing and DNS.
Feb 14 19:24:20 qidiziCentos NetworkManager[642]: <info> Activation (enp0s3) successful, device activated.
Feb 14 19:24:21 qidiziCentos avahi-daemon[531]: Registering new address record for fe80::a00:27ff:fe6a:55a4 on enp0s3.*.
Feb 14 19:24:56 qidiziCentos systemd: Starting Session 4 of user qidizi.
Feb 14 19:24:56 qidiziCentos systemd: Started Session 4 of user qidizi.
Feb 14 19:24:56 qidiziCentos systemd-logind: New session 4 of user qidizi.
Feb 14 19:24:56 qidiziCentos su: (to root) qidizi on pts/1
ps aux
[root@qidiziCentos qidizi]# ps aux
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.1 47464 3680 ? Ss 18:30 0:00 /usr/lib/systemd/systemd --switched-ro
root 2 0.0 0.0 0 0 ? S 18:30 0:00 [kthreadd]
root 3 0.0 0.0 0 0 ? S 18:30 0:00 [ksoftirqd/0]
root 5 0.0 0.0 0 0 ? S< 18:30 0:00 [kworker/0:0H]
root 6 0.0 0.0 0 0 ? S 18:30 0:00 [kworker/u2:0]
root 7 0.0 0.0 0 0 ? S 18:30 0:00 [migration/0]
root 8 0.0 0.0 0 0 ? S 18:30 0:00 [rcu_bh]
root 9 0.0 0.0 0 0 ? S 18:30 0:00 [rcuob/0]
root 10 0.0 0.0 0 0 ? S 18:30 0:00 [rcu_sched]
root 11 0.0 0.0 0 0 ? R 18:30 0:00 [rcuos/0]
root 12 0.0 0.0 0 0 ? S 18:30 0:00 [watchdog/0]
root 13 0.0 0.0 0 0 ? S< 18:30 0:00 [khelper]
root 14 0.0 0.0 0 0 ? S 18:30 0:00 [kdevtmpfs]
root 15 0.0 0.0 0 0 ? S< 18:30 0:00 [netns]
root 16 0.0 0.0 0 0 ? S< 18:30 0:00 [writeback]
root 17 0.0 0.0 0 0 ? S< 18:30 0:00 [kintegrityd]
root 18 0.0 0.0 0 0 ? S< 18:30 0:00 [bioset]
root 19 0.0 0.0 0 0 ? S< 18:30 0:00 [kblockd]
root 20 0.0 0.0 0 0 ? S 18:30 0:00 [khubd]
root 21 0.0 0.0 0 0 ? S< 18:30 0:00 [md]
root 22 0.2 0.0 0 0 ? S 18:30 0:11 [kworker/0:1]
root 24 0.0 0.0 0 0 ? S 18:30 0:00 [kswapd0]
root 25 0.0 0.0 0 0 ? SN 18:30 0:00 [ksmd]
root 26 0.0 0.0 0 0 ? SN 18:30 0:00 [khugepaged]
root 27 0.0 0.0 0 0 ? S 18:30 0:00 [fsnotify_mark]
root 28 0.0 0.0 0 0 ? S< 18:30 0:00 [crypto]
root 37 0.0 0.0 0 0 ? S< 18:30 0:00 [kthrotld]
root 38 0.0 0.0 0 0 ? S 18:30 0:00 [kworker/u2:1]
root 39 0.0 0.0 0 0 ? S< 18:30 0:00 [kmpath_rdacd]
root 40 0.0 0.0 0 0 ? S< 18:30 0:00 [kpsmoused]
root 59 0.0 0.0 0 0 ? S< 18:30 0:00 [deferwq]
root 82 0.0 0.0 0 0 ? S 18:30 0:00 [kauditd]
root 242 0.0 0.0 0 0 ? S< 18:30 0:00 [ata_sff]
root 248 0.0 0.0 0 0 ? S 18:30 0:00 [scsi_eh_0]
root 249 0.0 0.0 0 0 ? S< 18:30 0:00 [scsi_tmf_0]
root 251 0.0 0.0 0 0 ? S 18:30 0:00 [scsi_eh_1]
root 252 0.0 0.0 0 0 ? S< 18:30 0:00 [scsi_tmf_1]
root 260 0.0 0.0 0 0 ? S< 18:30 0:00 [kworker/0:1H]
root 321 0.0 0.0 0 0 ? S< 18:30 0:00 [kdmflush]
root 322 0.0 0.0 0 0 ? S< 18:30 0:00 [bioset]
root 340 0.0 0.0 0 0 ? S 18:30 0:00 [jbd2/dm-0-8]
root 341 0.0 0.0 0 0 ? S< 18:30 0:00 [ext4-dio-unwrit]
root 415 0.0 0.2 42992 4332 ? Ss 18:30 0:01 /usr/lib/systemd/systemd-journald
root 427 0.0 0.0 104452 1064 ? Ss 18:30 0:00 /usr/sbin/lvmetad -f
root 431 0.0 0.0 41984 1760 ? Ss 18:30 0:00 /usr/lib/systemd/systemd-udevd
root 490 0.0 0.0 0 0 ? S 18:30 0:00 [jbd2/sda2-8]
root 491 0.0 0.0 0 0 ? S< 18:30 0:00 [ext4-dio-unwrit]
root 499 0.0 0.0 51160 1768 ? S<sl 18:30 0:00 /sbin/auditd -n
root 507 0.0 0.0 80220 940 ? S<sl 18:30 0:00 /sbin/audispd
root 515 0.0 0.0 26188 920 ? S< 18:30 0:00 /usr/sbin/sedispatch
root 528 0.0 1.1 327532 21324 ? Ssl 18:30 0:01 /usr/bin/python -Es /usr/sbin/firewall
avahi 531 0.0 0.0 27944 1516 ? Ss 18:30 0:00 avahi-daemon: running [qidiziCentos.lo
root 532 0.0 0.8 549976 16076 ? Ssl 18:30 0:01 /usr/bin/python -Es /usr/sbin/tuned -l
root 533 0.0 0.3 273524 6820 ? Ssl 18:30 0:00 /usr/sbin/rsyslogd -n
root 542 0.0 0.0 34684 1736 ? Ss 18:30 0:00 /usr/lib/systemd/systemd-logind
dbus 544 0.0 0.0 26716 1688 ? Ss 18:30 0:00 /bin/dbus-daemon --system --address=sy
avahi 545 0.0 0.0 27944 444 ? S 18:30 0:00 avahi-daemon: chroot helper
root 546 0.0 0.0 126300 1600 ? Ss 18:30 0:00 /usr/sbin/crond -n
root 550 0.0 0.1 85068 2376 ? Ss 18:30 0:00 login -- qidizi
root 562 0.0 0.0 6484 324 ? Ss 18:30 0:00 /sbin/iprinit --daemon
root 564 0.0 0.0 6484 328 ? Ss 18:30 0:00 /sbin/iprupdate --daemon
root 574 0.0 0.0 39124 92 ? Ss 18:30 0:00 /sbin/iprdump --daemon
root 642 0.0 0.4 451924 9276 ? Ssl 18:30 0:01 /usr/sbin/NetworkManager --no-daemon
polkitd 686 0.0 0.5 514212 11244 ? Ssl 18:30 0:00 /usr/lib/polkit-1/polkitd --no-debug
root 1000 0.0 0.1 82792 3572 ? Ss 18:30 0:00 /usr/sbin/sshd -D
qidizi 2040 0.0 0.1 115348 2044 tty1 Ss 18:30 0:00 -bash
root 2064 0.0 0.1 189208 2676 tty1 S 18:30 0:00 sudo su
root 2065 0.0 0.1 180540 2156 tty1 S 18:30 0:00 su
root 2066 0.0 0.1 115452 2128 tty1 S+ 18:30 0:00 bash
root 2929 0.6 0.0 0 0 ? R 19:01 0:14 [kworker/0:2]
root 3507 0.0 0.2 133436 4804 ? Ss 19:20 0:00 sshd: qidizi [priv]
qidizi 3509 0.0 0.1 133436 2032 ? S 19:20 0:00 sshd: qidizi@pts/0
root 3510 0.0 0.1 189244 2700 pts/0 Ss 19:20 0:00 sudo su
root 3519 0.0 0.1 180548 2164 pts/0 S 19:20 0:00 su
root 3520 0.0 0.1 115352 2096 pts/0 S+ 19:20 0:00 bash
root 3646 0.0 0.2 133436 4804 ? Ss 19:24 0:00 sshd: qidizi [priv]
qidizi 3648 0.0 0.1 133436 2032 ? S 19:24 0:00 sshd: qidizi@pts/1
root 3649 0.0 0.1 189244 2712 pts/1 Ss 19:24 0:00 sudo su
root 3658 0.0 0.1 180548 2160 pts/1 S 19:24 0:00 su
root 3659 0.0 0.1 115352 2096 pts/1 S+ 19:24 0:00 bash
root 4062 0.0 0.8 104216 15688 ? S 19:38 0:00 /sbin/dhclient -d -sf /usr/libexec/nm-
root 4075 0.3 0.2 133436 4804 ? Ss 19:39 0:00 sshd: qidizi [priv]
qidizi 4077 0.0 0.1 133436 2032 ? S 19:39 0:00 sshd: qidizi@pts/2
root 4078 0.0 0.1 189244 2704 pts/2 Ss 19:39 0:00 sudo su
root 4087 0.0 0.1 180548 2164 pts/2 S 19:39 0:00 su
root 4088 0.0 0.1 115352 2064 pts/2 S 19:39 0:00 bash
root 4102 0.0 0.0 123356 1376 pts/2 R+ 19:39 0:00 ps aux
when network is working;ping some site,it is ok;
ping www.centos.org
PING www.centos.org (85.12.30.227) 56(84) bytes of data.
64 bytes from 85.12.30.227: icmp_seq=1 ttl=41 time=332 ms
64 bytes from 85.12.30.227: icmp_seq=2 ttl=41 time=354 ms
64 bytes from 85.12.30.227: icmp_seq=3 ttl=41 time=315 ms
^C64 bytes from 85.12.30.227: icmp_seq=4 ttl=41 time=308 ms
ifconfig
[root@qidiziCentos qidizi]# ifconfig
enp0s3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 10.0.2.15 netmask 255.255.255.0 broadcast 10.0.2.255
inet6 fe80::a00:27ff:fe6a:55a4 prefixlen 64 scopeid 0x20<link>
ether 08:00:27:6a:55:a4 txqueuelen 1000 (Ethernet)
RX packets 559 bytes 76566 (74.7 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 1257 bytes 268671 (262.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0

lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 0 (Local Loopback)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
before upgrade it is all OK (by "yum update");
when the "kernel" is update to this one ,the network is working then break ,minute by minute;


that is my tries,But the problem is still:

1 change "vm box" interface to another one(still);
2 stop firewalld(still);


may i try that?

1 reinstall "vm box"?
2 change network to "static"?


what can i do to debug the trouble?
thanks!


My English is very bad, sorry!

aks
Posts: 3054
Joined: 2014/09/20 11:22:14

Re: Network connection automatically keeps down and up

Post by aks » 2015/02/14 19:29:10

Looks like you have something called "link flap" (google it). Looks like the layer 2 link is up and then it goes down. This can happen for a handful of reasons, most of which are dependent of which networking technology you're using. Just google it, seriously.....

qidizi
Posts: 4
Joined: 2015/02/14 11:08:58

Re: Network connection automatically keeps down and up

Post by qidizi » 2015/02/15 09:00:48

aks wrote:Looks like you have something called "link flap" (google it). Looks like the layer 2 link is up and then it goes down. This can happen for a handful of reasons, most of which are dependent of which networking technology you're using. Just google it, seriously.....


when i shutdown all my network connector(wifi,lan),It still happens,But not so high frequency;Probably after some software on a network connection, it sends the packet to the port(vm box "NAT" ports),this time the "centos" use NAT(Network Address Translation),

It happened so quickly:icmp_seq=60
only when &quot;ICMP_SEQ=60&quot;, down/up happen;
only when "ICMP_SEQ=60", down/up happen;
QQ截图20150215161511.png (40.57 KiB) Viewed 20770 times
NAT,and settings
NAT,and some setting
NAT,and some setting
2.png (59.83 KiB) Viewed 20770 times

when i change to use "NAT network(global NAT?)",it never break(As I had written so many words when you look at it, it is normal:"64 bytes from 127.0.0.1: icmp_seq=2034 ttl=64 time=0.097 ms",the ssh client "putty" Connections have not been disconnected )
;
3.png
3.png (113.93 KiB) Viewed 20770 times
change "bridge connection","host-only",never break too;



However, I still don't know who sent the signal that is(NIC down/up,link-flap), and how to ignore the signal with centos setting,if i can't fix it.

thanks!

aks
Posts: 3054
Joined: 2014/09/20 11:22:14

Re: Network connection automatically keeps down and up

Post by aks » 2015/02/15 16:35:50

What is the host OS (the OS that vbox is running on)?

qidizi
Posts: 4
Joined: 2015/02/14 11:08:58

Re: Network connection automatically keeps down and up

Post by qidizi » 2015/02/15 17:59:43

window 7
QQ截图20150216020001.png
QQ截图20150216020001.png (68.97 KiB) Viewed 20744 times

aks
Posts: 3054
Joined: 2014/09/20 11:22:14

Re: Network connection automatically keeps down and up

Post by aks » 2015/02/16 17:14:25

I suspect this is a Windows problem then. Behind the virtual box software is a virtual switch (or bridge if you prefer). Something is telling that switch that the link has gone and that is propagating up to the virtual machine. I'm not a Windows expert, but would suggest looking in the event log(s). Aside from that, am not sure what else to try.

I don't think you can mask this kind of problem as it fundamental to networking, short of switching networking off inside the VM.

qidizi
Posts: 4
Joined: 2015/02/14 11:08:58

Re: Network connection automatically keeps down and up

Post by qidizi » 2015/02/24 02:58:56

aks wrote:I suspect this is a Windows problem then. Behind the virtual box software is a virtual switch (or bridge if you prefer). Something is telling that switch that the link has gone and that is propagating up to the virtual machine. I'm not a Windows expert, but would suggest looking in the event log(s). Aside from that, am not sure what else to try.

I don't think you can mask this kind of problem as it fundamental to networking, short of switching networking off inside the VM.

Thank you for your reply

Sher
Posts: 1
Joined: 2015/07/12 07:42:01

Re: Network connection automatically keeps down and up

Post by Sher » 2015/07/12 07:54:20

I'm having a similar problem and i did the following to fix it:

Code: Select all

$ systemctl restart networkmanager
$ systemctl restart network
$ ifdown <devicename, e.g. enp0s8>
$ ifup <devicename, e.g. enp0s8>

Post Reply

Return to “CentOS 7 - Networking Support”